This section provides background information related to the present disclosure which is not necessarily prior art.
Drain, waste, and vent (DWV) systems are used to move waste liquids and solids out of bathrooms and kitchens and into sanitary sewers by gravity. In addition to vent pipes, the drain or waste pipes of a DWV system can include a main and secondary stacks and smaller drain pipes coupled together. Historically, such DWV systems have used a combination of pipes of various sizes made from a variety of different materials joined together by many different methods.
Today, virtually all plumbing codes require that all pipes that are not exposed be permanently joined. Copper DWV systems use solder that can be reheated and cast iron “no-hub” systems use clamps that can be loosened; and therefore, are not actually permanently joined. Only thermoplastic pipe systems using compatible solvent mixtures can truly be considered to create a permanent joint that cannot be undone or reversed. Nevertheless, plumbing codes have refused to endorse the use of fitting components in DWV systems, primarily because they add appendages to existing systems and/or are not permanent connections.
Because DWV systems rely upon gravity flow and move both solid and liquid waste, they can be prone to clogging. Modern plumbing codes manage this problem by requiring access fittings such as clean-outs for unclogging the pipes. The inventors have realized that existing sanitary Tee and Wye fitting components can exacerbate this clogging tendency because they cause flow disruptions or disturbances at the resulting pipe intersection.